Oxidizing compositions for removing sulfur compounds from hydrocarbon fuels and wastewater

Abstract

An oxidizing composition for removing hydrogen sulfide (H 2 S) from a gaseous or liquid stream includes mixture products of water, sodium hypochlorite, a chelating agent, and a transition metal compound. The chelating agent can be etidronic acid; the transition metal compound can be an iron (III) compound, such as ferric sulfate. The oxidizing composition is formed by (i) combining water, chelating agent, and transition metal compound to form an activator composition and (ii) mixing the activator composition with a sodium hypochlorite solution to adjust the pH, such as for a particular use. Some embodiments include various apparatuses and methods for treating different treatment sites with the oxidizing compositions disclosed herein. Examples of suitable treatment sites include, without limitation, natural gas pipelines, bubble towers, oil wells, gas wells, sewer wet wells, air scrubbers, saltwater disposal pipelines, and saltwater disposal wells.

1 . A method for treating a saltwater disposal pipeline or saltwater disposal well comprising:
 providing a pre-mixed oxidizing composition in a first tank;   pumping the pre-mixed oxidizing composition into a first pipe;   pumping the pre-mixed oxidizing composition from the first pipe into a second pipe that connects to the saltwater disposal pipeline or to a well head of the saltwater disposal well;   monitoring pressure in the first pipe; and   activating and deactivating a pump that performs the pumping of the pre-mixed oxidizing composition into the first pipe to keep the pressure in the first pipe within a desired range.   
     
     
         2 . The method of  claim 1  further comprising:
 monitoring activation of a saltwater disposal pump that pumps saltwater to be disposed of into the saltwater disposal pipeline or the well head; 
 when the saltwater disposal pump is activated, activating a pump that pumps the pre-mixed oxidizing composition from the first pipe into the second pipe; and 
 when the saltwater disposal pump is not activated, deactivating the pump that pumps the pre-mixed oxidizing composition from the first pipe into the second pipe. 
 
     
     
         3 . The method of  claim 1  wherein the pre-mixed oxidizing composition comprises mixture products of water, sodium hypochlorite, a chelating agent, and a transition metal compound. 
     
     
         4 . The method of  claim 3  wherein the chelating agent comprises etidronic acid. 
     
     
         5 . The method of  claim 3  wherein the transition metal compound comprises an iron compound. 
     
     
         6 . The method of  claim 1  wherein the desired range for pH of the oxidizing composition is 10.0 to 10.3. 
     
     
         7 . The method of  claim 1  wherein the desired range for pH of the oxidizing composition is 8.8 to 9.7. 
     
     
         8 . The method of  claim 1  wherein the desired range for pH of the oxidizing composition is 8.0 to 9.8. 
     
     
         9 . The method of  claim 1  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.005-1.0 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated. 
     
     
         10 . The method of  claim 1  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.05-0.3 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated. 
     
     
         11 . A method for treating a saltwater disposal pipeline or saltwater disposal well comprising:
 providing a pre-mixed oxidizing composition in a first tank, wherein the pre-mixed oxidizing composition comprises mixture products of water, sodium hypochlorite, a chelating agent, and a transition metal compound;   pumping the pre-mixed oxidizing composition into a first pipe;   pumping the pre-mixed oxidizing composition from the first pipe into a second pipe that connects to the saltwater disposal pipeline or to a well head of the saltwater disposal well;   monitoring pressure in the first pipe;   activating and deactivating a pump that performs the pumping of the pre-mixed oxidizing composition into the first pipe to keep the pressure in the first pipe within a desired range;   monitoring activation of a saltwater disposal pump that pumps saltwater to be disposed of into the saltwater disposal pipeline or the well head;   when the saltwater disposal pump is activated, activating a pump that pumps the pre-mixed oxidizing composition from the first pipe into the second pipe; and   when the saltwater disposal pump is not activated, deactivating the pump that pumps the pre-mixed oxidizing composition from the first pipe into the second pipe.   
     
     
         12 . The method of  claim 11  wherein a desired range for pH of the oxidizing composition is 10.0 to 10.3. 
     
     
         13 . The method of  claim 11  wherein a desired range for pH of the oxidizing composition is 8.8 to 9.7. 
     
     
         14 . The method of  claim 11  wherein a desired range for pH of the oxidizing composition is 8.0 to 9.8. 
     
     
         15 . The method of  claim 11  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.005-1.0 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated. 
     
     
         16 . The method of  claim 11  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.05-0.3 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated. 
     
     
         17 . An apparatus comprising:
 a tank for holding a pre-mixed oxidizing composition comprising mixture products of water, sodium hypochlorite, a chelating agent, and a transition metal compound;   a first pump that pumps the pre-mixed oxidizing composition from the first tank to a first pipe at a first pressure;   a pressure sensor that detects the first pressure;   a second pump that receives the pre-mixed oxidizing composition from the first pump and pumps the pre-mixed oxidizing composition at a pressure higher than the first pressure to a saltwater disposal pipeline or saltwater disposal well head; and   wherein the first pump is activated in response to the pressure sensor to maintain the first pressure above a predetermined threshold, and the second pump is activated and deactivated to deliver the pre-mixed oxidizing composition to the saltwater disposal pipeline or saltwater disposal well head at a predetermined rate.   
     
     
         18 . The apparatus of  claim 17  further comprising a system controller that controls activation and deactivation of the first pump and second pump, monitors the pressure sensor, monitors activation of a saltwater disposal pump that pumps saltwater to be disposed of into the saltwater disposal pipeline or the well head, and when the saltwater disposal pump is activated, activating the second pump that pumps the pre-mixed oxidizing composition from the first pipe into the second pipe, and when the saltwater disposal pump is not activated, deactivating the second pump. 
     
     
         19 . The apparatus of  claim 17  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.005-1.0 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated. 
     
     
         20 . The apparatus of  claim 17  wherein a dosage of the pre-mixed oxidizing composition is in the range of 0.05-0.3 ml of pre-mixed oxidizing composition per 100 ml of saltwater being treated.